1. Field of the Invention
This invention relates to a rotary type air pressure filling system for filling tires with a specified air pressure in a tire assembly line in an automobile production line.
2. Description of the Prior Art
An air pressure filling system for tires in the automobile production line is adapted to fill tires with air pressure after a disk wheel is assembled to the tires in a tire assembly line, and the air pressure filling system usually includes a pressure control device to control the air pressure thus filled to a specified pressure and a conveyor to transfer the tires. This system is used for filling a tire having a tube with air pressure, or for bleeding air pressure from a tubeless tire (for example, air is extracted from a tire having an air pressure of 3.5 Kg/cm.sup.2 .about.4.0 Kg/cm.sup.2 to a specified pressure of 1.8 Kg/cm.sup.2) and so forth.
However, the air filling and air extracting by use of the conventional system takes much time, for example, requires about 60 sec. per tire. In consequence, to provde properly inflated tires for one vehicle (five tires) takes about 300 sec., thus resulting in reduced productivity to a considerable extent.
Now, to solve this problem, it has been the practice, as shown in FIGS. 1 and 2, to arrange a plurality of tires 101 in a line, and an operator 102 simultaneously performs the air pressure filling and air pressure extracting, thus trying to shorten the operating time.
FIG. 1 is a schematic plan view of an example of the prior art, and FIG. 2 is a schematic front view thereof. According to this method, a plurality of tires are arranged on a straight-line conveyor, and the operator 102 connects air hoses 103 extending from an air control device of the air filling system to the tires one by one to fill or extract the air pressure.
Since the plurality of tires are arranged in a straight line, in the case of tires of 14 inches radius, the distance from the first tire to the fifth tire amounts to about 3 meters, thereby presenting the disadvantage of wasting working time for the worker 102, who has to cover the distance for the connection of the hoses. In order to solve this problem, the tires should be reduced in number. However, if the tires are reduced in number, then the productivity declines.